Question 418447
the repulsive force between the north poles of 2 magnets is inversely proportional to the square of the distance between the 2 poles. 
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f = k/d^2
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Solve for "k" using "if the repulsive force is 40 pounds when the distance between the 2 poles is 2 inches"
40 = k/2^2
k = 160
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f = 160/d^2
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What is the repulsive force when the distance between the 2 poles is 4 inches?
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f(4) = 160/4^2
f(4) = 10 pounds
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Cheers,
Stan H.
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